AFTER eight months of rehabilitation, Ballina Seabird Rescue volunteers couldn't have picked a more perfect day to release Penny, the critically endangered Hawksbill sea turtle, back into the ocean.

Seabird Rescue general manager Kathrina Southwell said Penny had been severally underweight and suffering from float syndrome when she was brought in.

"She was in a terrible condition, a really poor condition," Ms Southwell said.

"She only weighed just under 4kg. She was way way skinny and really sunken underneath, and she wasn't eating for quite a while, while she was in care."

Penny was found in February by a local lady and her son who saw the turtle floating in the surf.

In addition to being underweight and suffering float syndrome, Penny was also covered in barnacles and algae.

Ms Southwell said she would only eat a small amount of prawns and seaweed in her first few weeks in care.

"The rehabilitation process consisted of giving her different types of medications and looking at her poo under a slide in the microscope and we actually found lots of micro plastic within her," she said.

"So that was pretty sad to see a critically endangered Hawksbill turtle suffering from plastic ingestion on such small pieces."

Penny the turtle released into the ocean:
Penny the Hawksbill Sea Turtle is released back into the ocean after being rehabilitated by Australian Seabird Rescue.

Float syndrome is a condition caused by plastic ingestion that leaves sea turtles unable to eat their normal diet as their bodies fill with gas preventing them from diving to the bottom of the ocean.

If left untreated, the animal will slowly starve to death or roast in the sun.

Ms Southwell said the rehabilitation process for Hawksbill Sea Turtles can be long, lasting anywhere between four and eight months.

"Eventually after she finished her medications, which was only about six weeks ago, she really started to put on weight and started eating between 400 and 500grams of prawns, squid and small baitfish. "

Penny was released at Flat Rock in Ballina at about 11.15am on Friday to a crowd of more than 150 spectators.

The Australian Seabird Rescue team are consistently urging everyone to make sure their trash doesn't end up in the ocean, and in the stomachs of marine life, by disposing of it responsibly.